Hi I have the same problem. I have Joomshopping version 4.0, dutch language pack 3.2.2.1 is installed, but after installing Jshopping cart, the language still is in English.
I've tried installing both Jshopping cart as Jshopping cart ext for Joomla 3+.

I do not know how to enter the ftp.

Can anybody help me in a way a beginner in computer language can understand?